With Some payment types (buy now pay later BNPY) the seller is charged up to 6% of the invoice value just to process the transaction. This fees is not onchargable to the customer. Credit card and Paypal are through Stripe at the nominated merchant fee cost - between 1-3%.
Items like gift vouchers at face value $100 incure the BNPL fee (non recoverable). This fee comes straight off bottom line/product margin.
When creating a new product or editing an existing one, an option for selecting payment types should be added. So if I do not want to accept BNPL on certian products with lower margins or face value items (gift cards) I can chose the payment options.